Indoor Air Quality

When most people talk about pollution, they are generally referring to the outdoor environment, that smog we’ve seen hovering above many cities worldwide. In Gallatin County, aside from the seasonal forest fires we tend to experience, we are lucky to have few problems with outdoor air pollution. But what many don’t realize is that indoor air pollution, in our homes and workplaces, is very common, and it can be extremely dangerous.

In fact, the Environmental Protection Agency (EPA) has estimated that the air inside can be as much as five times more polluted than the air outside. This is largely because of the furnishings decorative items we choose to surround ourselves, as well as the cleaning products we use.

As home owners, the first step is to understand—and eliminate—the sources of indoor air pollution. Some of the top issues include:

Mold: Molds are fungi that can grow and prosper in warm, damp environments. They spread and multiply through their spores, and there are thousands of varieties. Those sensitive to mold may experience nasal stuffiness, eye irritation, wheezing, or skin irritation. More severe reactions include fever and shortness of breath, and those with chronic lung illnesses may develop mold infections in their lungs.

Radon: Radon is a naturally occurring radioactive gas that may seep into your home from the soil or groundwater. Some homes in Gallatin County have been found to have elevated radon levels, and it is recommended that homes are tested for radon to determine if mitigation is needed.

Secondhand Smoke: Secondhand smoke is a mixture of the smoke given off by the burning end of a cigarette, pipe, or cigar, and the smoke exhaled by smokers. Secondhand smoke is also called environmental tobacco smoke (ETS) and exposure to secondhand smoke is sometimes called involuntary or passive smoking. Secondhand smoke contains more than 4,000 substances, several of which are known to cause cancer in humans or animals.

Carpets: Combinations of pet dander, dust mites, dirt, fungus, and other tiny particles hide in carpets and can contribute to lung irritation, allergies, and asthma. Carpet can also release cancer-causing chemicals, including formaldehyde. The American Lung Association actually suggests avoiding carpets altogether.

Paint: Lead paint, which was banned in the U.S. 30 years ago, is still present in many older homes. As it ages, cracks, and peels, it transforms into a poisonous dust that is harmful if inhaled or touched. Even contemporary paints release toxins that aren’t good for your health. The best way to avoid toxins is to choose paint that is labeled low-VOC or no-VOC (volatile organic compounds). When you paint, open windows and use fans to ensure proper ventilation.

Cleaning Products: Many cleaning products contain harmful chemicals, including chlorine, pesticides, and solvents. Instead, you can opt for “green” cleaners made with safe ingredients or search for recipes for homemade cleaning products online.

Wood Fixtures & Furniture: Some furniture, shelves, countertops, and other pieces that are made from pressed wood typically contain formaldehyde that have been known to “off-gas,” releasing the formaldehyde over time, effectively poisoning the air in your indoor environment. To prevent this, choose wood fixtures and furniture that are not made of pressed wood.

Air Purifiers: Oddly enough, the machines that are used to “purify” the air in an indoor environment can actually be extremely harmful by putting out large quantities of ozone. The primary component of smog, ozone can cause asthma attacks, coughing fits, and scarring on the lungs. If you feel compelled to use an air purifier, make sure to choose one that has not been included on a “buyer beware” list published by the California Air Resources Board; there were over 30 listed!


Although the Montana Department of Environmental Quality (MDEQ) has primary responsibility for air quality, the Environmental Health Services Department at the Gallatin City-County Health Department offers informational and educational support to the community on some air quality issues.


For more information, check out Educational Brochures.

If you have any questions please contact us at:

Environmental Health Services

215 West Mendenhall, Rm 108, Bozeman

(406) 582-3120